Brown rice may increase arsenic exposure, new study finds

Key Points:

• A new study finds that brown rice contains greater traces of toxic arsenic than white rice. 

• The researchers learned that brown rice grown both in the U.S. and internationally is more susceptible to arsenic exposure than white rice. 

• Overall, healthy adults shouldn’t worry about arsenic poisoning due to their brown rice consumption; the biggest risk is for children under the age of 5 and populations who consume the largest quantities of brown rice.   

While many consumers have opted for brown rice over white rice for health reasons, a new study conducted by researchers from Michigan State University may have you rethinking that choice. 

The researchers found that compared to white rice, brown rice contains larger traces of arsenic and inorganic arsenic concentration. 

“This research is important because it acknowledges the importance of considering food safety along with nutrition when consumers make choices about food,” senior investigator Felicia Wu said in a news release. 

“While we found that choosing brown rice over white rice would result in higher arsenic exposure on average, the levels should not cause long-term health problems unless someone ate an enormous amount of brown rice every day for years.”

The study

To understand the arsenic intake associated with different kinds of rice, the researchers analyzed recent studies that explored the nutritional makeup of rice. They also reviewed data from the “What We Eat in America” database from the U.S. Environmental Protection Agency and Joint Institute for Food Safety and Applied Nutrition. 

What are the health risks?

Ultimately, the researchers found that brown rice contains more arsenic and more inorganic arsenic concentration than white rice. This was true of rice grown nationally and globally. 

The researchers explained that organic arsenic tends to have fewer health risks, as the body can naturally expel it. However, inorganic arsenic is typically more toxic and harmful to the body. 

The proportion of inorganic arsenic in brown rice grown in the U.S. was 48% and 65% in brown rice grown globally. Comparatively, inorganic arsenic was 33% of the total arsenic makeup in U.S.-grown white rice grown and 53% of white rice grown globally. 

The researchers explained that arsenic gets into rice primarily because of the growing process. Arsenic gets absorbed into the soil, and because of the unique way that it is grown and cultivated, that absorption occurs at a much faster rate than with other grains. 

Are there health risks? 

For most healthy adults, the health risks associated with this kind of arsenic exposure are low. However, the researchers did identify some groups that this may be problematic for: children under the age of 5, populations that consume large quantities of rice, and those struggling with food insecurity. 

“If you’re consuming rice in the U.S., acute arsenic poisoning is not really a risk,” researcher Christian Kelly Scott said in a news release. “What we’re talking about is the chronic exposure, so over a long term. There’s cardiovascular, there’s risk to the endocrine system, and there’s an increased risk of diabetes associated [with] a longer-term exposure level.”

The researchers also encourage consumers not to immediately just cut brown rice out of their diets, as this issue is more complex than that. 

“This exposure assessment is only one side of the equation when examining the potential trade-offs between brown and white rice consumption,” Wu said. “Even if arsenic levels are slightly higher in brown rice than white rice, more research is needed to demonstrate if the potential risks from this exposure are mitigated in part by the potential nutritional benefits provided by the rice bran.”